If you work at a desk all day, it's important to train your upper back muscles to counteract the tendency to hunch your shoulders forward. This exercise strengthens the back of your shoulders and targets your rhomboids to improve your posture. This way your chest can stay lifted with your shoulders pulled back.

1. Stand with your feet hip-width apart and knees slightly bent. Grasp a weighted bar or a pair of dumbbells, turn your palms forward (facing them away from your body). Bend forward at the hips and raise your elbows behind you so that the bar or dumbbells situate near your hips. Lengthen your spine with your abdominals pulled in for support. Be sure to point your elbows backward and gaze slightly forward instead of looking straight down. Inhale.

2. Maintaining a long, straight spine, lower the weight until your arms are fully extended below your chest. On an exhalation, bend your elbows and raise the weight to the start position. Pause for 2 seconds and repeat 12 to 16 times. Rest for 30 seconds. For the second set, try turning your palms down (if you are using a bar) or turning your palms inward ( if you are holding dumbbells).

Voight is the creator of a line of fitness DVDs, including "Full Body Stretch" and "Ballet BodySculpt."

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